9:10 p.m. update: Storms have pushed east of the area and into the bay. It appears the storm risk is done for the evening, but we’ll keep an eye out in case. So far, one severe weather report has come in from the area, and that’s a 60 mph wind gust at Andrews AFB. The severe thunderstorm watch that has been cancelled except over eastern parts of the area should be fully cancelled shortly. Otherwise, it’s a muggy night with lows in the upper 60s to low 70s. Tomorrow brings less in the way of storm chances and heat, as highs rise to near 90 under mostly sunny skies.

5:40 p.m. update: Severe storms have been limited around the area thus far, but a few strong storms have developed, most notably in southern Prince William and northern Stafford counties heading east, and another in central Prince George’s and Anne Arundel counties also heading east. More scattered storms are possible over the next few hours and isolated ones could turn severe with damaging winds a threat.

Overview: A Severe Thunderstorm Watch has been issued for the entire Washington-Baltimore area until 10 p.m. It’s not clear how widespread storms will be - right now we believe chances are around 40% for any given location - but any storms that do form could produce heavy rain, strong to severe winds, and possibly hail. Best chance of storms looks to be 4-8 p.m.

Cause: An upper-level disturbance swinging through combined with the warm and moist air in place could trigger isolated to scattered strong to severe storms.